Customer:
Can I use this potentiometer with the following setup? I have a motor from a cordless hand drill that originally ran on a 3.6V battery. I’ve removed it and connected it to an 18650 battery to use as a small drill. Can I use a potentiometer to regulate the motor’s speed?
Original message (Croatian)
da li mogu koristiti ovaj potenciometar na sljedećem primjeru?
Imam elektromotor iz ručnog usisavača (radio je na baterije od 3.6V). Izvadio sam taj elektromotor i spojio sa 18650 baterijom te ću elektromotor koristiti kao malu bušilicu.
Da li mogu sa potenciometrom iz priloga regulirati brzinu vrtnje?
Hvala
Attachment omitted in migration: ScreenShot00132.png
Originally submitted via email support on 19 January 2018. Migrated to the forum for community visibility.
Soldered Support:
This potentiometer can only conduct a few mA of current, which means you cannot connect the motor directly. You will need a MOSFET between the potentiometer and motor.
Original message (Croatian)
ovaj potenciometar može provoditi struju od samo nekoliko mA, što znači da nećete moći direktno spojiti motor. Trebat ćete MOSFET između: https://i.ytimg.com/vi/ipiDHD4YEMM/maxresdefault.jpg
Dobar MOSFET za tu primjenu: https://i.ytimg.com/vi/ipiDHD4YEMM/maxresdefault.jpg
Customer:
Thanks for the answer. I haven’t had time to reply until now. I think in the end I might not need to connect the potentiometer because when I load the motor, the RPM drops significantly. Eventually, if I connect two 18650 batteries in series, then maybe I would need to use the circuit you suggested. But I first need to test how the motor will perform - whether it will spin twice as fast, although I actually want it to be twice as powerful, not twice as fast. Now the question is whether with this potentiometer I could get the same RPM as with one 18650 battery but have it be more powerful with two batteries.
Original message (Croatian)
hvala na odgovoru. Nisam stigao prije odgovoriti. Mislim da na kraju neću morati spajati potenciometar jer kada opteretim elektromotor okretaji dosta padnu. Evenutalno ako bi u seriju spojio dvije 18650 baterije, možda bi onda trebalo spojiti ovu shemu što ste predložili. Ali moram prvo testirati kako će onda elektromotor raditi, da li duplo brže iako bi ja zapravo htio da bude duplo jači a ne duplo brži… sada je pitanje da li bi sa ovim potenciometrom dobio istu vrtnju kao sa jednom 18650 ali da mi je jači sa dvije baterije.
Soldered Support:
It’s possible that your batteries cannot supply a large enough continuous current. You’ll encounter the same current problem even at higher voltage (connecting batteries in series) if current is your limiting factor. If it’s not a current issue, then increased voltage should increase RPM.
Original message (Croatian)
moguće da Vaše baterije ne mogu dati toliko veliku konstantnu struju. Isti problem sa strujom ćete imati i na većem naponu(tj. ako baterije spojite serijski) ako Vam je struja problem.
Ako nije, napon bi trebao povećati broj okretaja.
Customer:
What if I connect them in parallel? Then the voltage would stay the same since the RPM is fine, but I’m not sure what I’d gain from parallel connection in terms of current - just greater capacity or also more power, i.e., more consistent electron flow? With one battery it works well but the battery heats up quickly and power drops. When the battery cools down it works again, but the battery depletes quickly. The batteries are fine when used moderately - they have around 2000 tested mAh. Or should I connect them in series and use the potentiometer to regulate the voltage, but I don’t know how that affects motor power - for example, would I gain power with two batteries in series if I set the potentiometer to, say, 4V?
Original message (Croatian)
A da spojim paralelno, dakle napon bi mi ostao isti jer su mi okretaji ok, samo ne znam što bi paralelnim spajanjem dobio sa strujom, samo veći kapacitet ili i jači tj konstantnije kretanje elektrona. Sa jednom baterijom mi radi dobro ali se brzo baterija zagrije i padne snaga… kada se baterija ohladi opet dobro ali brzo se baterija potroši.. baterije su inače ok kada se umjereno koriste (imaju cca 2000 testiranih mah)
Ili da spojim serijski pa sa ovim potenciometrom reguliram napon, ali ne znam kako to ima utjecaja na snagu elektromotora, tj da li bi sa dvije baterije u seriji dobio na snazi u kombinaciji sa potenciometrom kojeg bi namjestio npr na 4V?
Soldered Support:
With parallel connection you’d get greater capacity, meaning longer runtime at maximum power. The batteries heat up because you’re drawing high current from them. To address this: distribute the load with more smaller batteries, cool the batteries, or draw less current. Those are your options.
It depends on the motor. Since it’s simple to test, I recommend trying it. That way you’ll learn the most.
Original message (Croatian)
Paralelnim spajanjem biste dobili veći kapacitet, tj. duže trajanje max rada. Baterije se griju zbog velike struje koju vučete iz njih. Rasporedite opterećenje s više manjih baterija ili hladite baterije ili vucite manju struju. Četvrtoga nema 
Ovisi o motoru. Budući da je jednostavno isprobati, preporučam taj način. Tako najviše i naučite/izvučete zaključaka
